Monitoring engine operation

Abstract

A method is provided for an engine. During this method, a database is provided for a parameter of the engine. The database includes a plurality of values for the parameter determined over a period of time. Confidence bands are established using a probability density function on the database. An action is performed in response to a comparison of a first updated value for the parameter to the confidence bands. The engine may be configured as a gas turbine engine or another type of heat engine.

What is claimed is: 
     
       1. A method for a heat engine, comprising:
 providing a database for a parameter of the heat engine, the database including a plurality of values for the parameter determined over a period of time; 
 establishing confidence bands using a probability density function on the database; 
 performing an action in response to a comparison of a first updated value for the parameter to the confidence bands; 
 predicting a trend for one or more future values of the parameter over a future period of time; and 
 performing a second action where the trend crosses an operating limit for the parameter. 
 
     
     
       2. The method of  claim 1 , wherein the heat engine comprises a gas turbine engine. 
     
     
       3. The method of  claim 1 , wherein the parameter is indicative of:
 a temperature within the heat engine; 
 a pressure within the heat engine; or 
 a rotational speed of a component within the heat engine. 
 
     
     
       4. The method of  claim 1 , wherein the plurality of values within the database are determined when the heat engine is operated at, or within a tolerance of, an operating condition. 
     
     
       5. The method of  claim 4 , wherein the operating condition is indicative of:
 an altitude; 
 a speed; 
 a temperature of ambient air outside of the heat engine; or 
 a temperature of air within the heat engine. 
 
     
     
       6. The method of  claim 1 , wherein the plurality of values within the database are determined when the heat engine is operated at, or within a tolerance of, an operating regime. 
     
     
       7. The method of  claim 6 , wherein the operating regime is indicative of:
 a power setting for the heat engine; 
 an angle of a vane within the heat engine; or 
 operation of another component operatively coupled to the heat engine. 
 
     
     
       8. The method of  claim 1 , wherein the plurality of values within the database are corrected for variability in operating conditions and/or variability in operating regimes. 
     
     
       9. The method of  claim 1 , wherein the confidence bands are established for between eighty percent and ninety-five percent confidence. 
     
     
       10. The method of  claim 1 , wherein the confidence bands are established for 3 sigma confidence. 
     
     
       11. The method of  claim 1 , wherein the action comprises updating the database to include the first updated value to provide a first updated database where the first updated value is within the confidence bands. 
     
     
       12. The method of  claim 11 , further comprising:
 establishing first updated confidence bands using the probability density function on the first updated database; and 
 performing a third action in response to a comparison of a second updated value for the parameter to the first updated confidence bands. 
 
     
     
       13. The method of  claim 1 , wherein the action comprises providing a notification where the first updated value is outside of the confidence bands. 
     
     
       14. A method for a heat engine, comprising:
 providing a database for a parameter of the heat engine, the database including a plurality of values for the parameter determined over a period of time; 
 establishing confidence bands using a probability density function on the database; 
 performing an action in response to a comparison of a first updated value for the parameter to the confidence bands; 
 predicting a trend for one or more future values of the parameter over a future period of time; and 
 performing a second action where a change in a slope of the trend is greater than a threshold. 
 
     
     
       15. A method for a heat engine, comprising:
 providing a database for a parameter of the heat engine, the database including a plurality of values for the parameter determined over a period of time; 
 establishing confidence bands using a probability density function on the database; 
 extrapolating the confidence bands over a future period of time to provide extrapolated confidence bands; 
 predicting a trend for one or more future values of the parameter over the future period of time; and 
 performing an action where the trend crosses one of the extrapolated confidence bands. 
 
     
     
       16. The method of  claim 15 , further comprising performing another action where at least one of
 the trend crosses an operating limit for the parameter; or 
 a change in a slope of the trend is greater than a threshold. 
 
     
     
       17. The method of  claim 15 , further comprising:
 receiving a first updated value for the parameter; and 
 performing an action in response to a comparison of the first updated value to the confidence bands. 
 
     
     
       18. The method of  claim 14 , wherein the parameter is indicative of:
 a temperature within the heat engine; 
 a pressure within the heat engine; or 
 a rotational speed of a component within the heat engine. 
 
     
     
       19. The method of  claim 14 , wherein
 the plurality of values within the database are determined when the heat engine is operated at, or within a tolerance of, an operating condition; and 
 the operating condition is indicative of
 an altitude; 
 a speed; 
 a temperature of ambient air outside of the heat engine; or 
 a temperature of air within the heat engine. 
 
 
     
     
       20. The method of  claim 14 , wherein
 the plurality of values within the database are determined when the heat engine is operated at, or within a tolerance of, an operating regime; and 
 the operating regime is indicative of
 a power setting for the heat engine; 
 an angle of a vane within the heat engine; or 
 operation of another component operatively coupled to the heat engine.